Characterization of nanocomposite films based on tomato seed mucilage, gelatin and TiO2 nanoparticles

Abstract

The aim of the present research was to investigate the interaction effect of incorporating titanium dioxide (TiO2) (0 %, 0.5 %, and 1 %) nanoparticles and manipulating the proportion of tomato seed mucilage (TSM) and gelatin (Ge) (1: 0, 0.33:0.67, 0.67:0.33, and 0:1) on the physical, mechanical, and microbial characteristics of the film. The findings indicated that the incorporation of TiO2 engendered an augmentation in the surface roughness of the film and an elevation in the film's thickness. The mechanical evaluation results revealed that the incorporation of TiO2 into the TSM-Ge films significantly enhanced (p˂0.05) the tensile strength (TS), (up to 300 %), an elevation of Young's modulus, while concurrently leading to a reduction in the elongation at break (EB). The incorporation of TiO2 resulted in a significant enhancement in various properties of the film (p˂0.05), including opacity, contact angle, oxygen permeability (OP), water vapor permeability (WVP), moisture absorption, moisture content, solubility, and swelling. The rise in the proportion of TSM resulted in a concomitant increase in the color differences (ΔE), and yellowness index (YI). Conversely, there was a decrease in the lightness (L*) and the whiteness index (WI). Additionally, an increase was found in opacity, solubility, moisture content, WVP, OP, swelling, and moisture absorption. It was observed that films without TiO2 exhibited no inhibitory effect. However, upon augmenting the concentration of TiO2 to 1 %, notable inhibitory and lethal effects were observed against various microorganisms, including Staphylococcus aureus, Escherichia coli, Aspergillus niger, and Candida glabrata. The results showed that the TSM-Ge composite film containing TiO2, exhibited potential as a viable choice for food packaging susceptible to microbial spoilage.